Steel converter

ABSTRACT

A steel converter is provided with a slag deflector secured to the slag skirt above each of the trunnion shafts. Each slag deflector has a ridge generally centered above the axis of the trunnion shaft and two sides diverging downwardly from the ridge. A first ring generally coaxial with each trunnion shaft extends from the outer periphery of the trunnion ring toward the adjacent trunnion shaft bearing and is movable with the trunnion ring. A stationary ring surrounds each of the first rings, but has an opening at the bottom. Most of the slag and steel blown out of the top of the converter is deflected away from the trunnion shafts and bearings by the slag deflectors. Any of this material which is deflected in such a manner that it enters the space between the two rings is crushed or broken when the converter is tilted and then discharged from the lower end of the rings.

[72] Inventor Harry W. Schurr, II Primary Examiner-Gerald A. Dost Moon Township, County of Allegheny, Pa. AttorneyMartin J. Carroll [21] Appl. No. 21,322

[22] Filed Mar. 20, 1970 [45] Patented Jan. 4, 1972 ABSTRACT: A steel converter is provided with a slag deflec- 73 Assignee U i States s l Corporation tor secured to the slag skirt above each of the trunnion shafts.

Each slag deflector has a ridge generally centered above the axis of the trunnion shaft and two sides diverging downwardly tied tates atet l 13,632,097

[54] STEEL CONVERTER from the ridge. A first ring generally coaxial with each trun- 7 Claims, 4Drawing Figs. nion shaft extends from the outer periphery of the trunnion [52] US. Cl 266/36 R ring toward the adjacent trunnion Shaft bearing and is mova' [51 1 in CI n C21: 5/50 ble with the trunnion ring. A stationary ring surrounds each of 501 Field of Search 266/35 36 first rings but has Pemng the P slag and steel blown out of the top of the converter is deflected away from the trunnion shafts and bearings by the slag deflec- [56] References Cit d tors. Any of this material which is deflected in such a manner UNITED STATES PATENTS that it enters the space between the two rings is crushed or broken when the converter is tilted and then discharged from 3,201,108 8/1965 Kramer 266/36 P the lower end ofthe rings Pmmmm 4m 31632.09?

SHEET 1 0F 2 io R INVENTOR HARRY W. SCHURR II By ha 4 A Home;

Pmmmm 41972 31632109"! SHEET 2 BF 2 IIVVEIVTOR HARRY I. SCHURR ML%.W

Attorney STEEL CONVERTER This invention relates to a steel converter and more particularly to apparatus for protecting the trunnion shafts and bearings from damage due to overflow or splattering of molten slag or steel. During the blowing of oxygen through the molten bath there is considerable splattering of slag and steel out of the mouth of the vessel which falls in many directions. It is common practice to provide slag skirts around the periphery of the converter vessel as shown by Menu US. Pat. No. 3,376,029 dated Apr. 2, I968, and Dellinger US. Pat. No. 3,427,081 dated Feb. l l, 1969. However, these skirts do not furnish sufficient protection and much hot slag and steel impinges on the trunnion shafts. in addition to possible damage to the surface of the shaft this increases the thermal stresses in the shaft. In addition the slag and steel may enter the trunnion bearings, thus burning out the bearing.

It is therefore an object of my invention to provide deflectors which direct the majority of the splattered slag and steel away from the trunnions and bearings.

Another object is to provide apparatus which further protects the trunnion shaft and bearing from slag and steel which may go over the top of the deflectors or be otherwise diverted toward the shaft or bearings.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIG. 1 is a sectional view of an oxygen steel converter having my invention incorporated therein;

FIG. 2 is an enlarged elevation of a portion of the converter of FIG. I with parts shown in section;

FIG. 3 is a view taken on the line IIIIII of FIG. 2; and

FIG. 4 is a view taken on the line IV-IV of FIG. 2.

Referring more particularly to the drawings, reference numeral 2 indicates a basic oxygen converter having a steel shell 4 lined with refractory 6 with a mouth or opening 7 at the top. Two aligned trunnion shafts 8 support the vessel and are rotatably received in bearings 10. One of the shafts 8 is rotated by a motor 12 through gearing 14. A trunnion ring 16 attached to the shafts 8 for rotation therewith completely encircles the vessel. A steel slag skirt 18 is attached to the shell 4 a short distance above the trunnions. This maintains cooling air ventilation clearance, maintains room for relative thermal expansion between the vessel and trunnion ring, and otherwise protects the trunnion ring. A steel heat shield 20 which extends from the bottom of the repair or service floor to the ground level protects the bearings and drives. The parts so far described are conventional.

According to my invention I provide a slag deflector 22 above the trunnion ring 16 at each trunnion shaft 8. The slag deflector 22 may be cast integral with the skirt 18, but is preferably made of steel plate welded to the skirt 18. The deflector 22 is generally triangular in shape having a ridge 24 substantially in the same vertical plane as the axis of the associated shaft 8 when the vessel is vertical. Sides 25 of the deflector diverge downwardly from the ridge 24. An outer ring 26 is secured to each heat shield 20 preferably by welding. The distance between the bottom ends of sides 25 is preferably greater than the diameter of outer ring 26. The ring 26 is continuous around at least the top half of the trunnion shaft 8 and preferably extends around the top 270 of the shaft as best shown in FIG. 4. This provides an opening 28 at its lower end for a purpose which will appear later. A flanged inner ring 30 is secured to the trunnion ring 16 as by welding and extends through the heat shield 20 with its flange 32 surrounding the shaft 8. The inside diameter of the ring 26 is approximately 2 inches greater than the outside diameter of the ring 30 so as to provide a gap or circumferential opening 34 approximately 1 inch wide between the rings. Of course, this dimension may vary somewhat without affecting the operation. A plate 36 is fastened to the base of the bearing 10 a short distance from the outside of the flange 32 and has a cutout upper portion 38 (FIG. 3) which conforms generally to the outside of the shaft 8.

In operation, the majority of foreign material such as slag or steel which splatters out of the mouth 7 of the vessel during blowing will be deflected by the deflectors 22 to one side or the other of shafts 8. However, a minor amount of this material will bounce off the heat shields 20 or otherwise work its way down into the opening 34 between the inner and outer rings. This material is mostly brittle and easily cracked. Thus, as the inner ring rotates around inside the fixed outer ring when pouring the heat, the surfaces of the rings crush the chilled foreign material which will fall out through the opening 28. The plate 36 prevents buildup of slag or metal which has dropped out of the opening 34 from entering the bottom part of the bearings 10.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

Iclaim:

1. In a steel converter having a pair of aligned bearings, a pair of aligned trunnion shafts one rotatably received in each bearing, a trunnion ring supported by said shafts for rotation therewith, said trunnion ring extending vertically above and below said shafts, a vessel for containing molten steel supported by said trunnion ring for movement therewith, a circumferential slag skirt secured to the outside of said vessel above said trunnion ring, said slag skirt extending downwardly and outwardly toward said bearings, and means for rotating said vessel about the axis of said shafts; the improvement comprising a pair of slag deflectors secured to said slag skirt one above each of said shafts, each of said slag deflectors having a ridge generally centered vertically above the axis of the associated shaft when the vessel is in a vertical position, and two sides diverging downwardly from said ridge.

2. A steel converter according to claim 1 including a first ring surrounding and generally coaxial with each of said trunnion shafts and extending from the outer periphery of said trunnion ring toward the adjacent bearing, a fixed ring spaced radially outward from each of said first rings and surrounding at least the upper half of the associated first ring with an opening at the bottom of the fixed ring, and a narrow gap between the fixed ring and first ring.

3. A steel converter according to claim 2 including a generally vertical heat shield surrounding each of said shafts between the adjacent bearing and said trunnion ring, said fixed ring being attached to said heat shield, each of said first rings extending beyond said heat shield toward the adjacent bearing, and a flange generally normal to said first ring secured to the outer end thereof and extending radially substantially to the adjacent shaft and outwardly beyond the fixed rmg.

4. A steel converter according to claim 3 including a generally vertical plate secured to each bearing base between said bearing base and flange and extending substantially to the lower part of the adjacent shaft.

5. In a steel converter having a pair of aligned bearings, a pair of aligned trunnion shafts one rotatably received in each bearing, a trunnion ring supported by said shafts for rotation therewith, said trunnion ring extending vertically above and below said shafts, a vessel for containing said steel supported by said trunnion ring for movement therewith, a circumferential slag skirt secured to the outside of said vessel above said trunnion ring, said slag skirt extending downwardly and outwardly toward said bearings, means for rotating said vessel about the axis of said shafts, a generally vertical heat shield surrounding each of said shafts between the adjacent bearing and said trunnion ring; the improvement comprising a first ring surrounding and generally coaxial with each of said trunnion shafts and extending from the outer periphery of said trunnion ring toward the adjacent bearing, a fixed ring spaced radially outward from each of said first rings and surrounding at least the upper half of the associated first ring with an opening at the bottom of the fixed ring, said fixed ring being attached to said heat shield with a narrow gap between the fixed ring and first ring.

6. A steel converter according to claim 5 including a flange 7. A steel converter according to claim 6 including a generally normal to said first ring secured to the outer end generally vertical plate secured to each bearing base between thereof beyond said heat shield toward the adjacent bearing, said bearing base f flange and extending substantially to the said flange extending radially substantially to the adjacent lower Pan Ofhe ad-lacent Shaft shaft and radially outward beyond the fixed ring. 5 

1. In a steel converter having a pair of aligned bearings, a pair of aligned trunnion shafts one rotatably received in each bearing, a trunnion ring supported by said shafts for rotation therewith, said trunnion ring extending vertically above and below said shafts, a vessel for containing molten steel supported by said trunnion ring for movement therewith, a circumferential slag skirt secured to the outside of said vessel above said trunnion ring, said slag skirt extending downwardly and outwardly toward said bearings, and means for rotating said vessel about the axis of said shafts; the improvement comprising a pair of slag deflectors secured to said slag skirt one above each of said shafts, each of said slag deflectors having a ridge generally centered vertically above the axis of the associated shaft when the vessel is in a vertical position, and two sides diverging downwardly from said ridge.
 2. A steel converter according to claim 1 including a first ring surrounding and generally coaxial with each of said trunnion shafts and extending from the outer periphery of said trunnion ring toward the adjacent bearing, a fixed ring spaced radially outward from each of said first rings and surrounding at least the upper half of the associated first ring with an opening at the bottom of the fixed ring, and a narrow gap between the fixed ring and first ring.
 3. A steel converter according to claim 2 including a generally vertical heat shield surrounding each of said shafts between the adjacenT bearing and said trunnion ring, said fixed ring being attached to said heat shield, each of said first rings extending beyond said heat shield toward the adjacent bearing, and a flange generally normal to said first ring secured to the outer end thereof and extending radially substantially to the adjacent shaft and outwardly beyond the fixed ring.
 4. A steel converter according to claim 3 including a generally vertical plate secured to each bearing base between said bearing base and flange and extending substantially to the lower part of the adjacent shaft.
 5. In a steel converter having a pair of aligned bearings, a pair of aligned trunnion shafts one rotatably received in each bearing, a trunnion ring supported by said shafts for rotation therewith, said trunnion ring extending vertically above and below said shafts, a vessel for containing said steel supported by said trunnion ring for movement therewith, a circumferential slag skirt secured to the outside of said vessel above said trunnion ring, said slag skirt extending downwardly and outwardly toward said bearings, means for rotating said vessel about the axis of said shafts, a generally vertical heat shield surrounding each of said shafts between the adjacent bearing and said trunnion ring; the improvement comprising a first ring surrounding and generally coaxial with each of said trunnion shafts and extending from the outer periphery of said trunnion ring toward the adjacent bearing, a fixed ring spaced radially outward from each of said first rings and surrounding at least the upper half of the associated first ring with an opening at the bottom of the fixed ring, said fixed ring being attached to said heat shield with a narrow gap between the fixed ring and first ring.
 6. A steel converter according to claim 5 including a flange generally normal to said first ring secured to the outer end thereof beyond said heat shield toward the adjacent bearing, said flange extending radially substantially to the adjacent shaft and radially outward beyond the fixed ring.
 7. A steel converter according to claim 6 including a generally vertical plate secured to each bearing base between said bearing base and flange and extending substantially to the lower part of the adjacent shaft. 